 The study examined the effects of adding desulphurized electrolytic manganese residue, DMR, to cement. It found that DMR can regulate the fluidity in water requirement for the normal consistency of cement, delay the hydration process of cement, increase the initial setting and final setting time of cement, and reduce the strength of cement mortar, especially the strength of early age mortar. Additionally, it was observed that the fineness of DMR had a significant impact on the strength of cement mortar. This article was authored by Shi Chao-Chun, Feng Wang, Li Wuma, and others.